Team:Duesseldorf

• Team ▾
  • Team
  • Collaborations
  • Meetup
  • On Tour
  • Attributions
• Project ▾
  • Description
  • Design
  • Experiments
  • Notebook
  • Model
  • Part Improvement
  • Characterization
  • Results
  • Demonstrate
  • Measurement
• Parts ▾
  • Parts Overview
  • Basic Parts
  • Composite Part
  • Part Collection
  • Part Improvement
  • Characterization
  • Validated Part
• Safety
• Human Practices ▾
  • Human Practices
  • Integrated Human Practices
  • Public Engagement
• Awards ▾
  • Medal Criteria
  • Integrated Human Practices
  • Education and Public Engagement
  • Entrepreneurship
  • Plant
  • Model
  • Measurement
  • Best New Basic Part
  • Best New Composite Part
  • Best Part Collection
• Judging Form

SynMylk

Efficient ✓ Microbial ✓ Eco-friendly ✓

Gold Medal ✓
Nominated for Best Education and Public Engagement ✓

The Problem

The increasing greenhouse gas emissions are a big issue for the future of the planet. Temperatures are rising, leading to numerous challenges we will need to face as humankind in the near future. One of the major contributors to climate change is large industrial livestock production for the dairy industry. Due to the daily use of dairy products, such as cheese on pizza or the glass of milk for breakfast, all of us contribute to the increase in greenhouse gas emissions. Our goal is essentially to create livestock-free milk, thereby overcoming the associated problems, but without having to change our diet and denying ourselves delicious dairy products.

The Right Chassis

For the production of our components, the organisms Escherichia coli, Bacillus subtilis, Pichia Pastoris and Synechocystis sp. PCC 6803 were modified. We chose multiple organisms because one of our aims was a high flexibility in the production process through modular choice of chassis. Furthermore, each organism of choice has unique valuable properties ideal for production, which can be used for an overall environmentally friendly and simple production.

Modeling

Before starting in the wet lab, we modeled what steps in the metabolism to modify in order to create a production strain able to produce our target chemicals at industrially relevant levels. This includes bottleneck enzymes limiting the flux toward fatty acids, as well as off-target candidates and enzymes involved in fatty acid degradation.

Experiments

An important component for the taste and the consistency of cow's milk is fat, composed of different fatty acid chain lengths. To produce the entire range of the required fatty acids, we applied different approaches from our modeling results.

overexpression of the ACC complex

heterologous expression of thioesterases

knock-downs of different enzymes
Milk proteins consist of several different proteins with important properties, like aroma retention and nutritional qualities. Furthermore, they contain all amino acids essential for the body in sufficient quantities. The desired proteins were heterologously produced in different organisms.

Human Practices

To recognize the larger issues at hand related to climate change, and share this with different groups of people outside of our lab, we started different projects beside our laboratory work. These projects gave us the opportunity to interact with a wide range of people in meaningful ways, including an education series in schools and foundations, a panel discussion, and much more.

The Solution

The “CraftMylk” part collection is suitable for the production and detection of milk proteins and fatty acids in different production hosts. It contains different promoter and terminator sequences to regulate the fatty acid or protein production in Synechocystis, Escherichia coli, Bacillus subtilis and Pichia pastoris. The collection contains coding sequences for thioesterases that can be expressed to alter fatty acid composition, and coding sequences for seven proteins which make up the largest protein portion in cow's milk. The “CraftMylk” collection contains guideRNA's to decrease the activity of genes that remove substrates like Acetyl-CoA from the synthesis cycle to increase the yield of target fatty acids in Synechocystis. It contains constructs which are involved in E. coli to increase the general amount of fatty acids. To analyse the fatty acid production, the toolkit contains building bricks (promoter, reporter, terminator) for biosensors to avoid costly analysis methods like GC-MS.